Well hole cleaner and method



Nov. 8, 1960 l. L. AuLT 2,959,224

WELL HOLE CLEANER AND METHOD Filed Sept. 30. 1957 United WELL HLE CLEANER AND METHOD Filed Sept. 30, 1957, Ser. No. 687,224

6 Claims. (Cl. 166-43) The present invention .relates to apparatus for and a method of cleaning the pipe falls surrounding the an- -nular space between ythe tubing and the casing in .a well bore, and, more particularly, relates to such apparatus and methods in which the apparatus is moved fbetween the 'tubing and casing by the application of Vfluidpressure against it thereby loosening the debris and .cleaning-the exposed walls of the `tubing and of the casing.

In the normal operation of an oil well, the space or annulus between the tubing and the casing becomes caked .with dir-t, drilling mud, and other material, commonly referred to `as junk in the trade. Considerable difficulty :has been encountered in cleaning the tubing and casing walls that enclose this annular space so that the well might vfunction as intended.

KIt is an Vobject of this invention to provide an im- .proved apparatus and method for loosening, .cleaning -and removing the `junk from between the tubing and casing in a well bore.

A further object of the present invention is the provision 'of an improved apparatus `adapted to be introduced into the annular space between the casing and vtubing'ofa well bore and, in response to pump pressure, 'be moved in this space .thereby cleaning and loosening the exposed pipe walls of junk.

Yet a still further object of the present inventionisthe provision 'of an improved apparatus for cleaning and removing debris and junk from between the casing and tubingina ywell'bore and which includes kmeans responsive to 'uid vpressure lso 'that it may be pumped downwardly in the annular space between the casing and the tubingv and by sreversing'circulation may bepumjped 11p- V-wardly in the annular space thereby dislodging, cleaning and pushing the TVjunk out from between Athe ycasingand the tubing.

Yet Va further object of the present inventionis the provision of such .an improved apparatus or, as `com- -monly referred to in the trade, a junk pusher, which is simple, eflicient and economical Vto use, construct and maintain.

`Yet a further object of the present invention is the provision of a method of cleaning the junk or debris collected in the annular space between the tubing and lcasing in a well bore by inser-ting an annular cleaner provided with a pressure-responsive element into this space and applying uid pressure against the pressureresponsive kelement thereby'moving the cleaner and cleaning the junk from between the casing and the tubing.

Yetra vfurther objectof this invention is the provision of an improved method of cleaning junk which includes inserting an annular cleaning assembly into the annular fspace between the casing and tubing in a well bore and pumping it down this space and thereafter reversing circulation and pumping it up the -space to dislodge and clean the junk or debris collected in the annular space.

Other `and vfurther objects, features and advantages Ytates Patent Vmay be secured thereto in any .preferred manner.

section l12a. `spaced scraper or wiper elements 28a extend outwardly from thebody v12a and yieldingly engage the inner surwill be :apparent from the following description of ra presently preferred .embodiment of the invention, `given for .the purpose of disclosure, and taken in conjunction with the accompanying drawing, wherelike character refferences designate like parts throughout ,the several views and where,l

Figure 1 Visl an v elevational view, in .quarter sectlon, illustrating'an apparatus according to the invention in position between .the tubing and casingordinarily disposedin a well bore, and

Figure 2 is a cross-sectional view taken along the line 2 2 of Figure 1.

Referring now to the drawings, and particularly to lFigure ,1, the reference numeral 10 generally designates `the kwelk-hole cleaner which ,includes a central ring-like vbody :section .14, which `might be termed the packer .or

piston Vsection-,of `the tool.v This Asection 14 has an annular, resilient .packer 16 'secured l,to its Aouter surface and anannular, resilient packer l7secured to -its inner surface.l It is noted that these packers are of the cuptype packers so that means are provided whichwill enable the cleaner to respond to pump pressure applied eithere1to the upper or lower areas lof the packers-16 and 17. VOf course,any preferred pressure responsive means may be used so that the well cleaner 10 may respond to and -be pumped up and down inthe annular space 119 between the vcasing 18 -and the tubing `20 disposed inthe well bore, not shown. The packers 16 4and 1-7 `may be secured to the central body section .14

in the recessed portions 13 and 15 provided to receive them in any preferred manner. It is noted that :the packers 16 and 17, in effect, forman annular, resilientpistonagainst which Huid pressure is directed to movefthe .cleaner 10 in the annulus 19.

Secured Ito each end of the central body section 14 are a vpair of ring-like, elongated body ysections 12a and 12b. .These are the scraper and wiper sections of the cleaner 10. As illustrated, these sections may be threaded to the central body section 14, although they For convenience'of manufacture, the body sections 12a and 12b -are identical kand may be interchanged.

For convenience of reference, identical numbers are appliedto bath of these sections except that the reference letter a has been added to the numbers'in the upperzsection andthe reference letter"b has been'added to thereference numerals in the lower section. Accordingly, in `describing Vthese sections, reference `will be vmadeto .the upper sesction, but it will be 4understood `thatltherlower section is identical and utilizes the same reference vnumerals with the exception that the reference letter b has been substituted for the reference letter a,

Turning now to the-upper scraper section, a plurality of elongate ywiper or scraper elements 24a are circumferentially -spaced about the body section 12a Aand are inwardly directed and yieldingly engage the outer surfaceof the'tubing 2li. These wiper or scraper sections 24a extend axially `a substantial length of the scraper Similarly, a plurality of circumferentiallyface-of the casing V18, asbest seen'in Figure 2. Preferablyfthednner scraper` or wiper elements 24a and outer wiper lelements 28a are circumferentially staggered in alternate relationship so that the scraper or wiper elements perform the dual function of scraping and wiping theltubing and casing and of maintaining the junk cleaner 'ina generallyaligned position with respect to the tubing y20VV and casing-18.

A plurality vofaxially extending slots or pockets '-2211 and 26a receive the elongate wipers or Scrapers 24a and 23a, respectively, and a plurality of springs 29a and 30a are provided in the pocketed portions of the Scrapers 24a and 28a so that these scrapers are yieldingly urged into engagement with the exposed surfaces of the tubing 20 and casing 18, as previously described.

In order to retain the `Scrapers 24a and 28a in the slots 22a and 26a, respectively, the stop rings 36a are welded or otherwise secured to the lower portion of the scraper section 12a and a stop ring 38a is threadedly secured to t-he upper end of this section, such as by the bolts 40. The projections or ears 35a are provided on each end of the scraper or wiper segments 24a and engage under the projecting shoulders of the stop members 36a and 38a, respectively.

In connection with the outer scraper elements 28a, these are shown in the lower section to which the reference letter b has been applied. It is noted that the retaining means for the outer scraper elements 28a are in all things identical to those described in connection with the inner `scraper or wiper segments 24a. Accordingly, no further description thereof is deemed necessary. The stop members 34a and 37a, however for these seg- `ments are illustrated in the upper portion of Figure 1.

It is noted that ythe stop ring 37a is welded to the upper scraper body member 12a and the stop ring 34a is a continuation of the upper cap 32a which is threadedly secured to the upper end of the upper body section 12a.

As mentioned previously, the lower wiper or scraper section 12b is constructed identically to that of the top section except that preferably the scraper sections are reversed or staggered with respect to the upper scraper section `so that substantially complete circumferential cleaning or scraping is accomplished.

It is noted that the scraper or wiper sections advantageously perform several functions. Since they are alternately spaced on the scraper body sections, they align the cleaner in the annulus 19. In addition, they permit considerable flexibility so that the cleaner will pass in many places which are not concentric, or which are restricted and the like. These scraper sections also provide a cleaning and scraping action on the accumulated junk between the casing and the tubing and provide substantially circumferential cleaning. If desired, of course, the wiper or scraper elements may be disposed at an angle to the axis of the tool, however, highly advantageous results have been obtained by the structure illustrated.

In use, the well cleaner is placed in the annular space 19 between the casing 18 and tubing 20. Fluid pressure, such as by pumps, is directed downwardly against the well cleaner 1G which forces the cleaner 10 downwardly in the annular space thereby scraping and cleaning the exposed walls of the casing 18 and tubing 20, the packers 16 and 17 serving as a pressure responsive means or annular piston. After bottom has been reached, the circulation is reversed so that fluid is pumped down the tubing and back up through the annular space 19 which causes or forces the well cleaner 10 to be moved up the annular space 19. During such movement, of course, the exposed walls are again scraped and cleaned and the junk is pushed ahead of the well cleaner.

Ordinarily, a pressure indicating device, not shown, is rused in connection with the pumps and a sharp rise in pressure indicates when bottom and top is reached or when the cleaning tool is in danger of becoming stuck.

It is noted that the center or packer section provides a resilient seal in the annulus 19 and serves as a flexible piston so that the cleaner 10 moves in response to pump pressure directed either to the upper part of the piston or the lower part thereof. This exible annular piston and seal is sufficiently resilient to permit the tool to pass through restrictions in the annulus, such as caused by a pipe joint 42. It should be noted also, that the annular packer or exible piston aids in the cleaning of the annulus by rubbing against the exposed walls of the casing 18 and tubing 20 and by serving to accumulate and carry along the loosened junk.

It will be understood that the cleaning tool 10 includes the omission of one of the cleaning or scraper sections. With only one such section, satisfactory scraping and cleaning may be performed. It will be understood, however, of course, that any number of scraper and packing sections may be used, as desired.

It is believed that the method of the invention is apparent from the foregoing description of a presentlypreferred apparatus of the invention. The method, however, comprises the steps of introducing an annular cleaning assembly in the annular space between the casing and tubing, or other pipes', in a well bore, the cleaner assembly having a pressure responsive element, and directing tluid pressure against the pressure responsive element thereby moving the cleaner assembly in the annular space thereby scraping and cleaning debris from the walls thereof. The method also comprehends pumping, such as applying pump pressure to the fluid in the annular space, the cleaner assembly down the annular space and reversing circulation by pumping uid down the tubing and directing it to the underside of the cleaner assembly thereby pumping it up the annular space to perform the cleaning function and to remove the cleaner and debris from the well bore.

The present invention, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned as well as others inherent therein. While a presently preferred embodiment of the invention is given for the purpose of disclosure, numerous changes in details of construction, arrangements of parts and steps of the process may be made which will readily suggest themselves to those skilled in the art which are encompassed within the spirit of the invention and the scope of the appended claims.

What is claimed is:

1. Apparatus for cleaning the exposed walls between coaxially disposed pipes in a well bore comprising, an elongate annular body adapted to be moved between said pipes, pressure-responsive means secured to the body and adapted to engage the walls of the pipes, a plurality of scraper elements yieldingly secured to the body and adapted to engage exposed walls of the pipes, and means connected to said pipes for applying fluid pressure between said pipes whereby application of fluid pressure to the pressure-responsive means moves said apparatus thereby scraping said exposed walls.

2. Apparatus for cleaning the walls surrounding the annulus between pipes disposed in a well bore comprising, an elongate annular body adapted to be moved in the annulus, a resilient packer mounted and arranged on said body so as to engage the walls of the pipes, a plurality of scraper elements yieldingly secured to the body and adapted to engage exposed walls of the pipes, and means connected to said pipes for applying fluid pressure between said pipes whereby application of uid pressure to said packer moves said apparatus in the annulus thereby cleaning said exposed wa.ls.

3. Apparatus for cleaning the walls between pipes in a well bore comprising, an elongate annular body adapted to be moved longitudinally between said pipes, said body having a plurality of longitudinally-extending and circumferentially-spaced slots, scraper elements yieldingly secured in said slots and adapted to engage and scrape exposed surfaces of said pipes, a resilient annular piston secured to said body and adapted to engage the exposed walls of said pipes, and means connected to said pipes for applying fluid pressure between said pipes whereby application of uid pressure against said annular piston moves Said apparatus thereby scraping said exposed walls.

4, Apparatus for cleaning the walls surrounding the annulus of pipes disposed in a well bore comprising, an

elongate annular Ibody adapted to be moved in the annulus, said body provided on its outer and inner surfaces with a plurality of longitudinally-extending and circumferentially-spaced slots, said slots on the inner surface being circumferentially staggered with respect to those on the outer surface, a plurality of Scrapers yieldingly secured in said slots and adapted to engage exposed walls of said pipes, an annular resilient packer secured to said body and mounted and arranged for engaging said exposed walls, and means connected to said pipes for applying fluid pressure between said pipes whereby lapplication of fluid pressure against said packer moves said apparatus in said annulus thereby scraping. and cleaning said exposed Walls.

5. Apparatus for cleaning the walls surrounding the annulus of pipe disposed in a well bore comprising, an elongate annular body adapted to be inserted into and moved in the annulus, an annular piston secured to the central portion of said body for engaging exposed walls of said pipes, a scraper assembly secured to the body on each side of said central portion, each said scraper assembly provided with a plurality of alternate inwardly and outwardly extending slots spaced circumferentially about the body, a scraper element yieldingly secured in each slot and yieldingly engaging said exposed walls, and means connected to said pipes for applying liuid pressure between said pipes whereby application of uid pressure to said annular piston moves said apparatus in 6 said annulus thereby scraping and cleaning the exposed walls.

6. The method of cleaning debris from the inner Wall of casing in `a well bore and the outer wall of tubing disposed within the casing, said inner wall and outer wall defining an annular space comprising, inserting an annular cleaner into said annular space engaging the inner and outer walls, applying iiuid pressure above and to said cleaner through said annular space thereby moving said cleaner downwardly in said annular space and cleaning the Walls, and then applying fluid pressure through the tubing and into the annular space below the accumulated debris and to the bottom of said cleaner thereby moving the cleaner and the accumulated debris upwardly in said annular space to the surface of the well.

References Cited in the file of this patent UNITED STATES PATENTS 1,758,945 Armstrong et al. May 20, 1930 2,203,966 Otis June 1l, 1940 2,298,975 Shelburne Oct. 13, 1942 2,318,696 Linden May 11, 1943 2,475,160 Stamos July 5, 1949 2,661,065 McCoy Dec. l, 1953 2,728,398 Taylor Dec. 27, 1955 2,802,535 Taylor Aug. 13, 1957 

